(1) Field of the Invention
The present invention relates to a method and device for inputting information for a portable information processing device: more specifically, it relates to a method and device for inputting information by touching keys displayed on the screen with a pen.
(2) Description of the Prior Art
Pen input portable information processing devices are getting more and more popular these days. FIG. 1 is an example of the outward appearance of such a portable information processing device. In order to create a document or a directory, an operator of portable information processing device 10 touches keys on a virtual keyboard (hereinafter referred to as just "keyboard") displayed on screen 30, using a pen.
FIGS. 2A and 2B are examples of screen layouts, showing the input method for a conventional portable information processing device. FIG. 2A shows a screen layout for inputting Japanese characters, while FIG. 2B shows a screen layout for inputting English characters and numerals. By switching between these two types of screens when necessary, various types of characters can be inputted.
Specifically, the screen of this device is divided into four display areas: text edit area 201 for displaying a text to be edited; conversion area 202 for converting a set of kana (phonetic Japanese characters) into kanji (Chinese characters); control key area 204 for giving various control indications; and character designation area 203 for designating input characters. The operator can create or edit a document, by using a pen to touch keys displayed on character designation area 203 and control key area 204.
Suppose that a kana keyboard is displayed on character designation area 203 as shown in FIG. 2A. By touching a pen to (QWERTY) in control key area 204, character designation area 203 changes to the one shown in FIG. 2B. Likewise, when a QWERTY keyboard is displayed in character designation area 203 as shown in FIG. 2B, it changes to the one shown in FIG. 2A by using the pen to touch (Kana) in control key area 204.
As is mentioned above, according to a conventional portable information processing device, various types of key input are possible with a small screen by switching display between various types of keyboards.
However, the conventional input method has the following disadvantages.
(1) Repeatedly applying pressure to the display screen causes hard strain for the operator. It should be noted here that the creation of a document including, for example, Japanese characters, English characters, and numerals, requires switching screens more frequently than the creation of a document comprising only English characters and numerals.
Also, if the operator has touched a pen to a wrong key, he or she has to touch a pen to (Delete) in control key area 204, because the wrong input key will have been determined the moment the pen touched the key.
Furthermore, in order to designate related characters having different attributes (upper/lower case characters in English or voiceless/voiced sound or p-sound in Japanese), further pen operations are needed. Specifically, in order to input a lower case letter from the keyboard in FIG. 2B, it is necessary to touch a key in character designation area 203 and then (Convert) in control key area 204.
Generally speaking, in handwriting, human beings are more used to horizontal movement of the hand over the manuscript rather than vertical movement. Therefore, repeated vertical movement causes strain on the operator's hand.
(2) As there are many keys on the screen, is easy for the operator to press the wrong key. For example, since 50 phonetic characters called "kana" are necessary to input Japanese, the size of each key on a kana keyboard, such as that shown in FIG. 2A, is extremely small. Therefore, if the operator tries to touch a pen to a desired key quickly, it is easy for the operator to input a wrong key. Especially, when the operator uses the device on his or her palm in the open air, stability is bad and display is unclear. Therefore, he or she is likely to input wrong keys.